Phonograph-record-recording machine



May 7, 1929. H. PFANNENSTIEHL 1,711,650

PHONOGRAPH RECORD RECORDING MACHINE Filed Dec. 24, 1925 2 Sheets-Sheet l May 7, 1929. H. PFANNENSTIEHL 1,711,650

PHONOGRAPH RECORD RECORDING MACHINE Filed Dec. 24, 1925 2 Sheets-Sheet 2 Patented May 7,: 1929.

UNITED STATES PATEN HARRY PFANNENSTIEHL, or MAPLEWOOD, NEW'JERSEY, ASSIGNOR "r0 WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW NEW YORK.

yonx, n. Y., A 'conronarron or PHONOGRAPH-REOORD-RECORDING MACHINE.

Application filed December 24, 1925. Serial No. 77,475.

This invention relates to phonograph record recording machlnes and more speclfically to a machine for recording phonographrecords of the type used in connection with talking moving picture reproducing machines, and the like.

In the phonograph records heretofore used for reproduction in synchronism with picture records or films, the spiral grooves which define the path of the reproducer needle were cut with a uniform pitch, each successive groove being necessarily as close The object of this invention is the pro Vision of a recording machine in which the beginning of the groove which starts at the center of the disc is cut in a manner'to permit the operator to easily place the reproducer needle at the exact starting point in the recorded groove, thereby assuring the reproduction of the picture and the sound record in exact synchronism.-

A feature of the invention is the provision of a mechanism whereby a spiral groove of a relatively coarse pitch is made at the beginning of the recordin operation. together with means whereby this mechanism is rendered ineffective during the remainder of the recording operation, during which period the groove spiral is cut with a much greater number of turns per inch.

Another feature is the provision of a mechanism for moving the recorder carriage by a hand wheel pinion and -rack,and for automatically controlling the meshing and unmeshing of the nut with the lead screw to avoid any possibility of the fine thread on the nut. or lead screw from being damaged while the recorder carriage is being moved by hand.

Other features of invention and advantages will appearfrom the followin descriptions and by the claims appended thereto, reference being had to the accompanying drawings in which p Fig. 1 is a front assembly view of cording machine embodying the features of this invention.

Fig. 2 is a sectional view of the machin taken approximately 011 line 2-2 of Fig. 1

and looking in the direction indicated "by".

the arrows.

. Flg. 3 is-a partial assembly view showing the follower nut screw in position when the shaft of the-stylus returning mechanism is moved in position shown in Fig. 2. Fig. 4c is a top assembly view of the machine showing the starting position of the coarse pitch spiral mechanism in section. Hg. 5 is another sectional View of the coarse pitch spiral mechanism showing the position of the cam when in operated position, and

Fig. 6 is a portion of a disc recorded'by means of the machine embodying the features of this invention.

Similar reference characters refer to similar parts throughout this description.

The machine of this invention preferably consists of a heavy rectangularly shaped base 10', Fig.1, provided at one end portion with a perpendicularly extending support 11 which may be either secured on the top plane surface of the base by means of. ordinary screw bolts or cast integrally with the base.

On this support is mounted an electric motor T oFI- icE. I

the re- 12, the armature shaft of which is disposed at right angles with respect to the top plane surface of the base 10. On the upwardly extending end portion of the motor shaft is mounted a phonograph turntable 13 which'is provided with a plurality of equally spaced pads or hearing members 14 and a felt disc 15 on which the record disc 16 is adapted to rest. On the base 10 and adjacently disposed .to support 11 is mounteda bench 17 disposed in line parallel with respect to the length of base 10. This bench is provided with a ta l o le 18 along which a carriage 19 is adapted to be moved by means of a power driven lead screw 20 and a manually operable mechanism shown in Figs. 2, 3 and handwheel or crank 23 in the well known manner. This carriage is provided with a bracket 24 which extends laterally therefrom for supporting the recording apparatus as shown in Fig. 1 which may be of the type disclosed in the application of Henry G. Harrison, filed May 5, 1924, Se rial No. 711,044. The carriage 22 and the recording apparatus may be moved in a vertical direction for adjusting-the stylus 25 of the recording apparatus with respect to the phonograph record 16 on the turntable 13. The carriage 22 may be locked in position by means of a set screw 26. In the right-hand portion of carriage 19 there is mounted a follower nut screw 27 which is normally held in engagement with the lead screw 20 by means of a spring 28 which has one end portion in abutment against the under surface of angle piece 29 and the other end portion against the follower nut screw as shown in Fig. 3. The lead screw 20 is journaled at one end portion in bracket 30 and the other end portion in a bushing 31 which in turn is supported in a bracket 32. Each of these brackets is preferably formed integrally with the bench 17. Bushing 31 is slidably arranged in the bracket 32 but held against rotation therein by means of a key which extends in engageable relation in the longitudinally disposed slot 34 in the periphery of the bushing. The lead screw 20 is held against lateral movement in the bushing by means of a shoulder portion 35 formed by the enlarged portion of the lead screw and an adjustable collar 36 provided with a set screw 37 for locking the collar in adjusted position. Bushing 31 is provided with an aperture 38 shown in Figs. 4 and 5 which cooperates with plunger 39 for locking the bushing 31 when brought in position as shown in Fig. 5 and thereby preventing any accidental longitudinal movement of the lead screw 20. Plunger 39 is slidably mounted in bracket and is held resiliently in engageable relation with the aperture 38 by means of a spring 40. A knob 41 is provided for disengaging the plunger from aperture 38 and thereby releasing the bushing '31 for a purpose that will be hereinafter described.

Bracket 32 is provided with a lug 42 which extends laterally therefrom and on which roller 43 is mounted. This roller is disposed in engageable relation with a side cam 44 and cooperates therewith to impart an axial movement to the lead screw 20 and a corresponding movement to the carriage 19 coupled thereto upon the starting'of the motor 12. The cam 44 is interiorly screw-threaded and fits the reinforced portion 35 to permit the adjustment of the cam 44 with respect to its associated roller 43 where it may be securely held by means of screws 56 and 57. I I The motion of motor 12 is transmitted t the lead screw 20 by means of a belt 47 which passes over a train of pulleys 45 and 46, which are disposed at right angles one with respect to the other and each of a diameter as to give the proper speed ratio between the turntable 13 and the lead screw 20. The belt 47 also passes over two guide pulleys 67, only one of which is shown in Fig. 1, the other being symmetrically located on the far side of the pulley 46 and thence over pulley 48 which is journaled on the forked plunger 49 after which it passes over the pulley 48 supported in any suitable manner on the bench 17. Plun er 49 is slidably mounted in 3. lug 51 preferably integrally formed with the bench 17, and a spring 51, acting on the plunger 49 is provided to hold the belt constantly at the proper.tension and thereby prevent any slipping of the belt on the pulleys during the recording operation.

The manually operated mechanism for returning the carriage and the stylus carried thereby to the starting position near the center of the record consists of a handwheel or crank 71 mounted on one end of a rotatable and axially movable shaft 52 which is journaled in bushings 8 and 9 in the carriage 19 and disposed at right angles with respect to the longitudinal axis of lead screw 20. On the other end portion of this shaft is securely mounted a spur gear 53 adapted to be moved'in mesh with an associated stationary gear rack 54 which is disposed in line parallel to the movement of carriage 19 and securely held on the bench 17 by means of a number of screws such as 55 shown in Fig. 2. On the middle portion of shaft 52 there is securely mounted a conical member or cam 58 disposed in engageablc relation with the arm 59 of a trigger 60. This trigger is pivoted at 61 in the carriage 19 and extends therefrom into a recess 62 in the follower nut screw 27 in such a manner that when the shaft 52 is moved axially to the position indicated by the dotted lines shown in Fig. 2, i. e., to the position wherein the pinion 53 meshes with the rack 54, the cam 58 causes the trigger to lift and disengage the follower nut screw 27 from the lead screw 20, thereby permitting the free movement of the car riage 19 along the table 18 and the adjustment of the stylus 25 at any distance from the center of the disc 16 through the rotation of crank 71. It will be noted that the recorder carriage cannot be moved by the crank 71 until the nut is clear of the lead screw thread, thereby avoiding any possiof set screw 26.

bility of the fine thread onthe nut and lead screw being damaged while. the recorder carriage is being moved by hand.

On carriage 19 there is mounted a pointer member 63 for cooperating with a graduated scale 64 mounted on the bench 17 to indicate accurately the distance between the center of the record and the stylus 25.

The recording operation is effected as follows:

A disc 16, on which the sound is to be recorded is laid properly on the turntable 18 and the shaft 52 is moved to the position wherein the pinion 53 carried thereby engages the gear rack 54 and the follower nut screw 27 is disengaged fifom the lead screw 20. The carriage 19 carrying the recording apparatus in its raised position is then moved manually by the crank 71 toward the center of the disc-16, the proper distance being indicated by the position of the pointer 63 adjacent the scale (34. The carriage 22 is then lowered until the stylus engages the disc 16 in whichposition it is secured by means The lead screw 20 and the cam 41 carried thereby are then moved manually by the knob 66 until the roller 43 registers with the depression 65 of cam 44: as shown in Figs. 1 and 4.

Upon the starting of the motor 12 and the turntable 16 connected thereto, the shaft 52 having been withdrawn so that the follower nut screw 27 now engages the lead screw 20,

' the side cam 44 is effective to move the lead screw 20, the carriage 19 and the recording stylus 25 a distance equal to the raise of side cam 44. Aperture 38 of the bushing 31 is broughtinto registry with plunger 39 which automatically engages the bushing 31 for locking the lead screw. From this point on the carriage l9 and the recording device mounted thereon continue to move according to the pitch of the lead screw 20 to the completion of the recording operation. During the effective movement of side cam 44 the carriage moves a linear distance of about thus causing the stylus 25 to out two grooves with relatively large clearance surfaces between them, as shown in Fig. 6. The grooves thus generated by this mechanism greatly assist in placing the needle of a reproducing apparatus at the exact starting point of the sound record when reproduced in connection with moving picture machines,-

where anexact synchronism is necessary.

What is clalmed 1s: 1. In a. machine for making sound records,

a turntable adapted to support a disc, a motor for operating said turntable, a stylus, manually operable means for moving said stylus with respect to said disc, and power driven means, operated from a source of power operating at a constant speed, to automatically move said stylus at a plurality of speeds while said turntable and disc are moving at a constant speed.

2. In a. machine for making sound records, the combination with a recorder carriage, means for driving said carriage comprising a follower nut and lead screw, means for manually moving said carriage comprising a handwheel and rack and pinion, said pinion being movable to mesh with said rack, of means automatically operated by the move ment of the pinion in meshing with the rack for disengaging said nut from said screw prior to the meshing of said pinion with the rack.

3. In a phonograph recording machine, a turntable for carrying a recording disc, a stylus, a manuallyoperated mechanism for moving said stylus into engagement with the recording disc, a motor for driving said turntable, and a mechanism operated from said motor for automatically recording on the disc turns of different pitch.

4. In a phonograph recording machine, a turntable adapted to support a disc, a motor for operating said turntable, a stylus, a plurality of manually operable means movable at right angles, one with respect to the other,

'for adjusting said stylus with respect to the disc, power driven means for operating said stylus for making a record groove on said disc and means on said power driven means for making the first few turns of the record groove of greater pitch than the remaining turns.

5. In a recording machine, a turntable adapted to support a phonograph 'disc, a stylus associated with said disc, a bench, a carriage slidably mounted on said bench for supporting said stylus, a lead screw, means for operatively connecting said carriage to said screw, a motor for driving said turntable and screw, a cam carried by said screw, and anabutment on said bench cooperating with the cam to impart a bodily movement tosaid lead screw for moving said carriage along said bench.

, In witness whereof, I hereunto subscribe my name this 15th day of December, A. D.

HARRY PFANNENSTIEHL. 

